Electro-osmotical filter-press.



B. SCHWERIN.

ELECTRO OSMOTICAL FILTER PRESS.

APPLICATION FILED APR. 8. 1913.

1 1 1 H1l+ 11;[ H

Patented 001. 12, 1915.

an sra'rns PATENT o Boar-Ho sonwn'nm, or FRANKFORT-ON-THE-MAIN, GERMANY, ASSIGN'OR TO GESELL- SCHAF'I. rim ELEKTRO-OSMOSE M. B. 3., or FRANKFORT-ON-TZHE-MAIN, GERMANY,

A. CORPORATION.

ELEcrRo-osMorIcAL FILTER-PRESS.

Patented Oct. 12, 1915.

Application filed April 8, 1913. SeriaLNo. 759,798.

T 0 all whom it may concern:

Be it known that I, Bo'rno Sonwnam, residing at Frankfort-on-the-Maln, 'Germany, Improvements in an Electro-Osmotlcal Filtor-Press of which the following is a specification.

There are a large number of substances such as peat, clay, kaolin and the like from which water or other liquid cannot be entirely removed by mechanical means, or

- only with extreme difiiculty. Filter presses of previously known construction have worked fairly satisfactorily as long as the solidparticles in suspension are comparatively large grained. But they operate less and less satisfactorily and with increasing expense the finer the particlesbecome and when the colloidal size of particles is' reached these filters are quite impossible, sinceas the degree of fineness of the particles increases, the pressure used must be correspondingly increased, and as the pressure increases, more filter cloths are used and more energy 1s expended.

The present invention relates to a filter press by using of which theliquld is extracted by electrical-osmosis in conjunction with more or less mechanical pressure or suction. 1

The invention is shown in the accompanymg drawmgs.

igure -1 IS a View, partly in vert cal section, partly m-vertical section, partly in ele- .rated from. each other by partitions vation. ,Fig. 3 is a vertical sectional view vention shown in Fig. 1, and Fig. 4. is a view similar to Fig. 3 of the modification. Fig.

5 is a detail view showing the'connections of the feed pipes. v r .The press (Figs. 1 and 3). consists of a numberv ofvchambers (4) which are sofa- 1 Each chamber contains electrodes 6), which are insulated from the filter press and perforated and which may be, when desired,

covered with filter cloths .(9). The suspension is conveyed to the chambers by the tubes (2) and (3), which connect with the interior-byslits (5) in such a manner, that the suspension is surrounded by the-electrodes. There are corresponding openings have invented certain new and useful.

hard lead.

v (10) provided in the outer part of the chambers which allow the discharge from the press of the liquid which has been pressed through the filter cloths and electrodes, while the solid material is detained between the electrodes in the middle part of the chambers.

The joining of the electrodes ((5) to the p, and (3 and the current is switched on. Un-

der the influence of the pressure and the electro-osmotic effect of' the current the mass between the electrodes getsjlesiccated and the water flows off through the openings (10). -Duringthis process the substance is pumped in under slight pressure, according to the amount of water removed,

, untilthe compact matter left has attained the desired degree of dryness. Then after the current has been switched ofl' and the hydraulic pressure released, the press is emptled 1n the usual manner.

In Figs. 2-and 4 another form of the pres ent invention is shown. Here each chamber contains-a?non-perforated electrode (11) and on both sides -of same two perforated electrode }(6( which, as in Fig. 3 may again be covered with filter cloths 9. In this way tWochamber-s=(-12) and (13) are formed, in

.whichthe drying process takes place in the same manner asfin the chambers (4) of Fig.

3. Filter cloths 9 and electrodes 6' are similar to the corresponding elements in Fig.

1. The partitions between the chambers are designated 1. The particles deposit on the filter-cloths as the liquid passes out through the perforated electrodes. The particles also settle in the bottom of the chambers between the cloths.

Whenall the electrodes of the same sign are connected in parallel so that there'is' no difference in potential between the same, the

electrodesdo not have to be insulated from the body of the filter press, it is then sulficient to insulate the electrodes ,ofthe other sign fromthe press.

The electrodes are made preferably of With the present filter press only a very small pressure is required compared to that usually employed. Whereas in previously known methods pressures up to 20 atmospheres have been necessary, with the present press the pressures may be reduced, even to 1 atmosphere and under certain conditions suction may be used instead.

hen treating peat, clay or chalk according to the present invention, ferric hydroXid and other substances separate out at the electrode toward which the water migrates generally the cathode and gradually chokes the press by preventing the escape of water. This disadvantage can be obviated by reversing the flow of current after each or several charges. The deposited substances are then freed or migrate in the opposite direction into the cakes of compressed material and are removed with these. The reversing of the current can be made in the well known manner by using a changing switch in the leads. (14 in Fig. 1.)

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, what I claim, is:

1. An electro-osmotical filter press comprising perforated electrodes defining therebetwcen a space of constant volume, means to supply electric current to the electrodes, means to supply a suspension to the space.

2. An electro-osmotica'l filter press com prising perforated electrodes defining therebetween a space, means to pass current between the electrodes, means to supply suspension to the space, the electrodes being stationary to keep the space at constant volume.

3. An electro-osmotical filter press comprising perforated electrodes, defining a space of constant Volume, meansto pass current between the electrodes, means to supply suspension to the space, filter cloths mounted on the adjacent sides of the electrodes.

4. An electro-osmotical press comprising perforated electrodes defining therebetween a space of constant volume, means to pass current between the electrodes, means to supply suspension to the space, and means to hold the electrodes and the suspension therebetween against movement.

5. An electro-osmotical filter press comprising a pair of perforated electrodes, an electrode locked between said pair, means to charge the pair at a potential different from the electrode between the pair, there being defined between the pair of electrodes a space, means to supply a suspension to the space. J

6. An electro-osmotical filter press comprising a pair of perforated electrodes, filter cloths on the adjacent sides ofthe electrodes,

. an electrode located between the cloths,

means to supply a suspension to the space defined between the cloths, and means to charge the pair of electrodes at a potential different from the potential of the electrode between the cloths, the electrodes being held stationary.

7. An electro-osmotic filter press comprising spaced electrodes providing a chamber of constant capacity, and means for introducing a suspension into the chamber, said electrodes permitting the passage of liquid therethrough.

In testimony whereof I affix my signature in presence of two witnesses.

BOTHO SCHWERIN.

Witnesses JEAN GRUND, CARL GRUND. 

